Pump-pressure regulator



Feb. 19, 1963 J. G. ZUBATY ETAL 3,077,921

PUMP-PRESSURE REGULATOR Filed 001;. 17, 1960 INVENTORS fl A NORA/6yUnited States Patent Office 3,077,921 Patented Feb. 19, l9d3 3,077,921PUM'RPRESSURE REGULATOR Joseph G. Znbaty, Flint, and Harold A. Haven,Fenton,

Mich, assignors to General Motors Corporation, Detroit, Mich, acorporation of Delaware Filed (lot. 17, 1960, Ser. No. 62,938 2 Claims.(Cl. 15836.4)

The present invention relates to a unique pump and pressure regulatordevice. More specifically, the present device includes a pump andgovernor mounted on a drive shaft disposed generally at right angles toa pump operating arm. The governor is adapted to control a fuel pressureregulating valve such that the pressure output from said device isproportional to engine speed. Further, the pump operating arm is sorelated to the drive shaft that as the back pressure against which thepump is working increases, the pump stroke will be decreased to reducethe pump output.

Specifically, the subject pump, per se, is generally of the type shownin Patent 2,640,424 of Babitch and includes a diaphragm controlled by anactuating member functioning in conjunction with an eccentric devicewhich retracts the diaphragm to charge the pump chamber and spring meanswhich moves the diaphragm in a pump discharging direction. In thepresent invention, the dia phragm actuating arm includes a portionenlarged with respect to an eccentric formed on the drive shaft wherebypump back pressure can cause the diaphragm and acmating arm to moverelative to the eccentric and thereby decrease the pump stroke as saidpressure increases. The drive shaft actuates a flyball governor devicesuch that the latter acts through spring means to control an axiallyspaced pressure regulating valve whereby the pressure output of saidpump is controlled in accordance with engine speed.

The details as well as other objects and advantages of the presentinvention will be apparent from a perusal of e detailed descriptionwhich follows.

in the drawings:

FIGURE 1 is a sectional view of the subject pumppressure regulator; and

FIGURE 2 is a view along line 22 of FIGURE 1.

Referring to FIGURE 1, the pump-pressure regulator is indicatedgenerally at 16* and includes a drive shaft 12 supported on bearings 14and 16 respectively disposed within casing members 1% and Shaft 12. isrecessed at 22 to receive any suitable power input member 24. Casing 2%includes a chamber 26 in which governor device 23 is disposed. As willbe considered subsequently in greater detail, governor 23 is mounted onand driven by drive shaft 12.

A pump mechanism is indicated generally at 38' and, except for theunique manner in which the pump is driven by and coacts with a driveshaft 12, is of the type shown in the aforenoted Babitch patent.Briefly, the pump includes a flexible diaphragm 32 peripherally clampedbetween casing 2t} and an additional casing 34. Fuel inlet and outletchambers are designated at 36 and 38 and include valve members 40 and 42which permit said chambers to be communicated as the diaphragm isactuated. As the diaphragm is retracted or raised inlet valve 49 isopened to draw fuel from fuel inlet chamber 36 into pumping chamber 44.At the same time, outlet valve 42 is closed to prevent fuel from beingdrawn back through outlet chamber 38 into the pumping chamber 44. On theother hand, as the diaphragm is depressed or lowered, inlet valve 46will close and outlet valve 42 will open permitting the volume of fuelcontained within chamber 44 to be forced through outlet chamber 38 andto be discharged through outlet passage 46. As thus far described, pump30 is substantially the same as the aforenoted Babitch pump.

A diaphragm 47 is dis-posed in outlet chamber 38 and moves slightly withvariations in pressure to eliminate in part pressure waves in thesystem.

An actuating arm or member 43 includes a first portion 58' centrallyengaging diaphragm 32. Member 48 includes a second portion 52articulated through pin 54 to first portion 5%. The upper end of pumpactuating arm portion 5.2. is enlarged to provide an oblong innersurface 56 adapted to coact with an eccentric portion 53 formed on driveshaft 12. As best seen in FIGURE 2, as shaft 12 rotates, eccentricportion 58 will engage with actuating arm surface 56 causing the same tobe raised against the force of springs oil and '62. Casing 29 in cludesa chamber 64 within which spring members 69 and 6?; are seated and whichalsobias against a diaphragm reinforcing member 66 to urge the diaphragmin its dis charge direction. As eccentric 58 moves to its uppermostposition, arm 48 and diaphragm 32 will be raised to the retractedposition in which pump chamber 44 is filled with fuel. Thereafter, asthe eccentric continues to rotate, springs as and 62- will urge arm 48downwardly maintaining surface 56 in contact with the eccentric and atthe same time causing fuel to be discharged through outlet chamber 38.

inasmuch as the inner surface 56 of actuating arm portion 52 isconsiderably larger than eccentric 58, it is apparent that as the backpressure in pump chambers 38 and 44 increases, for reasons which will besubsequently considered in greater detail, springs 6i) and 62 are notable to return diaphragm 32 to its full discharge position. As aconsequence, the pump stroke and hence pump discharge is reduced. Inthis way, the capacity of the pump is variable so as to supply thatquantity of fuel determined by certain other operating conditions.

It is apparent that other lost motion arrangements may be providedbetween shaft eccentric 58 and diaphragm 32. For instance, surface 56 ofarm portion 52 could be made to engage on opposite sides with eccentric5'8, i.e. no lost motion at this point of articulation. Instead, thelost motion connection could be between diaphragm 32 and actuating armportion 5G Referring now to governor device 23, it will be seen thatshaft 12 includes a portion 7% extending beyond bearing 36 into chamber26. A flyweight separator cage 72. is fixed to shaft portion 7% forrotation therewith and is adapted to confine flyweights '74 so thatrotation of shaft 12 will cause the flyweights to be moved radiallyoutwardly in accordance with centrifugal force. A dishshaped member 76is mounted on shaft portion 70 so as to be freely movable axiallyrelative thereto as flyweights 74 move radially outwardly. Dish-shapedmember 76 in cludes a sleeve portion 78 adapted to support a ballbearing member 8%. A collar 82 is fixed to the outer race of bearing 89.Bearing 8t permits dish-shaped member 76 to rotate relative to collar82'.

Collar 82 includes an axially extending boss 84 which supports one endof a spring member 36, the other end of which biases against a flexiblediaphragm 88 peripherally clamped between valve casing 96 andintermediate casing 92.. Intermediate casing 92 is suitably secured tocasing 2% through studs 94 to enclose governor chamber 26.

Diaphragm 88 is a part of a pressure regulator mechanism indicatedgenerally at 96. Pressure regulator 96 is contained within the casings@tl and 92 and includes an outlet chamber 98 and an inlet chamber 100.Inlet chamber 1% is actually formed by an end cap member 192 and a valveseat member M4 each adapted to be suitably threaded within casing 96.Inlet chamber 1W receives the output from pump 3t through passage 46.

Inlet and outlet chambers 100 and 98 are adapted to communicate throughvalve seat member 104. A ball valve member 106 coacts with seat member104 to regulate the pressure in outlet chamber 98,

One end of a spring 198 is supported within end cap H92 and the otherend biases ball valve member 106 against seat member 104. A web 11% isformed in casing 90 and includes a central opening therethrough toslidahly support a pin member 112 centrally secured to diaphragm 88. Theother end of pin 112 is adapted to engage ball member 1% to urge thesame oft" its seat against the force of spring 103. Thus governorcontrolled spring 86, through diaphragm 38 and pin T112, and fuel outletpressure tend to unseat ball member 106 while spring 1% and fuel inletpressure tend to seat the hall member.

With the engine stopped and the parts in the position shown in FIGURE 1,spring 86 will predominate and maintain ball member 106 off its seat. Asthe rotative speed of shaft 12 progressively increases, flyweights '74will move outwardly urging dishrshaped member '76 axially to the left toincrease the force of spring 86 and thereby move ball member 196 further01f its seat permitting fuel to pass from inlet chamber 1% to outletchamber 98. As the speed of shaft 12 increases the opening of ball valvemember 106 permits progressively higher pressure fuel to be dischargedfrom outlet chamber 9% through discharge opening 114. There is arestriction downstream of the device consisting of a metering needle andorifice, not shown, which regulates the fuel flow to the engine. Due tothis restriction, the fuel pump builds pressure almost immediately whichwill act on diaphragm 88 and cause valve 1% to clase, thus reducing thepressure in chamber 98 to a predetermined value depending on the speedof shaft 12 and governor device 28.

Collar 82 may be moved axially by member 76 and flyweig-hts 74 until itengages an axially extending abutment 116 formed on intermediate casing92. Under these conditions, ball valve 106 will be fully opened and thefull output pressure of pump 30 will be discharged through outletopening 114. As already noted, as valve memberltid is movedprogressively toward a more closed position, with decreased rotativespeeds of shaft 12, the back pressure in pressure regulator chamberinlet chamber and passage 46 will be increased thereby reducing theoutput of pump to an amount comptatible with the demand of the system inwhich the subject device is incorporated.

We claim:

1. A combination pump and pressure regulator comprising casing means, ashaft rotatably support-ed within said casing means, a pump disposed insaid casing means, said pump including a flexible diaphragm, anactuating arm centrally fixed to said diaphragm and disposed atsubstantially right angles to said shaft, an eccentric portion formed onsaid shaft, said actuating arm including an enlarged portion having asurface adapted to coact with said eccentric, said surface being largerthan said eccentric portion whereby a clearance is provided betweenportions of said surface and said eccentric, first sprnig means urgingsaid diaphragm in a discharging direction tending to maintain saidsurface in pumping engagement with said eccentric, pump output pressurebeing adapted to act against said diaphragm to move said arm surfacerelative to said eccentric to vary the stroke of said pump, a pressureregulator device, conduit means communicating the output side of saidpump with said device, said pressure regulator device including an inletchamber communicating with said conduit means and an outlet chamber, avalve member controlling flow between said inlet and outlet chambers,second spring means urging said valve member in a direction tending torestrict flow between said chambers, and a centrifugal governing devicecoaxial with and driven by said shaft adapted to urge said valve memberin an opening direction with a force proportional to the speed of saidsharft.

2. A combination pump and pressure regulator as claimed in claim 1 inwhich the centrifugal governing device includes speed responsive meansmounted on said shaft, sleeve means slidably mounted on said shaftintermediate speed responsive means and the second spring means, thespeed responsive means being adapted to move the sleeve means toward thesecond spring member with a force proportional to the speed of saidshaft.

References Cited in the file of this patent UNITED STATES PATENTS11,708,306 Giesler Apr.'9, 1929 2,485,525 Bedale Oct. 18, 1949 2,515,074Bobier luly 11, 1950 2,640,424 Babitch June 2, 1953 2,764,996 Brown Oct.2, 1956 2,871,844 Elliott et a1. Feb. 3, 1959 2,992,530 Chadwick July'18, 1961 FOREIGN PATENTS 549,205 Great Britain Apr. 7, 1942

1. A COMBINATION PUMP AND PRESSURE REGULATOR COMPRISING CASING MEANS, ASHAFT ROTATABLY SUPPORTED WITHIN SAID CASING MEANS, A PUMP DISPOSED INSAID CASING MEANS, SAID PUMP INCLUDING A FLEXIBLE DIAPHRAGM, ANACTUATING ARM CENTRALLY FIXED TO SAID DIAPHRAGM AND DISPOSED ATSUBSTANTIALLY RIGHT ANGLES TO SAID SHAFT, AN ECCENTRIC PORTION FORMED ONSAID SHAFT, SAID ACTUATING ARM INCLUDING AN ENLARGED PORTION HAVING ASURFACE ADAPTED TO COACT WITH SAID ECCENTRIC, SAID SURFACE BEING LARGERTHAN SAID ECCENTRIC PORTION WHEREBY A CLEARANCE IS PROVIDED BETWEENPORTIONS OF SAID SURFACE AND SAID ECCENTRIC, FIRST SPRING MEANS URGINGSAID DIAPHRAGM IN A DISCHARGING DIRECTION TENDING TO MAINTAIN SAIDSURFACE IN PUMPING ENGAGEMENT WITH SAID ECCENTRIC, PUMP OUTPUT PRESSUREBEING ADAPTED TO ACT AGAINST SAID DIAPHRAGM TO MOVE SAID ARM SURFACERELATIVE TO SAID ECCENTRIC TO VARY THE STROKE OF SAID PUMP, A PRESSUREREGULATOR DEVICE, CONDUIT MEANS COMMUNICATING THE OUTPUT SIDE OF SAIDPUMP WITH SAID DEVICE, SAID PRESSURE REGULATOR DEVICE INCLUDING AN INLETCHAMBER COMMUNICATING WITH SAID CONDUIT MEANS AND AN OUTLET CHAMBER, AVALVE MEMBER CONTROLLING FLOW BETWEEN SAID INLET AND OUTLET CHAMBERS,SECOND SPRING MEANS URGING SAID VALVE MEMBER IN A DIRECTION TENDING TORESTRICT FLOW BETWEEN SAID CHAMBERS, AND A CENTRIFUGAL GOVERNING DEVICECOAXIAL WITH AND DRIVEN BY SAID SHAFT ADAPTED TO URGE SAID VALVE MEMBERIN AN OPENING DIRECTION WITH A FORCE PROPORTIONAL TO THE SPEED OF SAIDSHAFT.